feat: Add experimental http3 support

Only enabled in Docker builds for now, due to build config required. Not
sure if more work is needed for 0RTT.

Cargo.lock

@@ -1857,6 +1857,12 @@ dependencies = [
  "zune-inflate",
 ]
 
+[[package]]
+name = "fastrand"
+version = "2.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "37909eebbb50d72f9059c3b6d82c0463f2ff062c9e95845c43a6c9c0355411be"
+
 [[package]]
 name = "fax"
 version = "0.2.6"
@@ -2157,6 +2163,34 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "h3"
+version = "0.0.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "10872b55cfb02a821b69dc7cf8dc6a71d6af25eb9a79662bec4a9d016056b3be"
+dependencies = [
+ "bytes",
+ "fastrand",
+ "futures-util",
+ "http",
+ "pin-project-lite",
+ "tokio",
+]
+
+[[package]]
+name = "h3-quinn"
+version = "0.0.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b2e732c8d91a74731663ac8479ab505042fbf547b9a207213ab7fbcbfc4f8b4"
+dependencies = [
+ "bytes",
+ "futures",
+ "h3",
+ "quinn",
+ "tokio",
+ "tokio-util",
+]
+
 [[package]]
 name = "half"
 version = "2.7.1"
@@ -3919,6 +3953,7 @@ checksum = "b9e20a958963c291dc322d98411f541009df2ced7b5a4f2bd52337638cfccf20"
 dependencies = [
  "bytes",
  "cfg_aliases",
+ "futures-io",
  "pin-project-lite",
  "quinn-proto",
  "quinn-udp",
@@ -4171,6 +4206,8 @@ dependencies = [
  "futures-core",
  "futures-util",
  "h2",
+ "h3",
+ "h3-quinn",
  "hickory-resolver",
  "http",
  "http-body",